Hypothalamus manufactures and secretes hypothalamic regulatory hormones which control the secretion of adenohypophysial hormones. It is also the site for the synthesis of the two neurohypophysial hormones. Several of these hypothalamic hormones possess unique structural features - carboxamide groups at the C-terminal and 5-oxoprolyl (pyroglutamyl) residues at the N-terminal. The proposed research is aimed at characterizing the enzymatic processes which are responsible for the synthesis of these terminal groups. It is proposed that the enzymes be purified and their various properties investigated.